Table 3.
Acid mixturea | Recovery (%) | |||
---|---|---|---|---|
HNO3 | HNO3:H2SO4 (1:1) | HNO3:H2SO4 (1:2) | H2SO4 | |
360 μg | 21 ± 1 | 87 ± 4 | 94 ± 3 | 86 ± 3 |
Digestion timeb | 15 min | 30 min | 45 min | |
36 μg | 87 ± 4 | 81 ± 5 | 93 ± 5 | |
360 μg | 94 ± 3 | 92 ± 6 | 97 ± 4 | |
Digestion temperaturec | 190°C | 210°C | ||
36 μg | 93 ± 5 | 92 ± 3 | ||
360 μg | 97 ± 4 | 103 ± 1 | ||
360 μg | 97 ± 4 | 103 ± 1 |
Temperature-190°C/time-15 min
Temperature-190°C/acid mixture-H2SO4 & HNO3 (2:1)
Time-45 min/acid mixture-H2SO4 & HNO3 (2:1)